JULY 15--Nikon's Semiconductor Inspection Technologies Group (Melville, NY; www.nikonusa.com) has introduced its most advanced overlay measurement system to the US market. The NRM-3000 provides automatic measurement of overlay and NSR focus marks with the highest speeds and exceptional precision. The NRM system features a high-precision, dedicated optical system with exceptional aberration management. The Nikon objective lens is designed specifically for overlay measurement and offers high signal-to-noise ratio and high dynamic range.
The illumination system is bright and optically matched to the imaging system. It uses a fiberoptic delivery system to an efficient and affordable quartz-halogen lamp. The user can easily replace the lamp without the need for any complicated or specialized procedures.
The NRM-3000 uses an actively damped stage and a new EGA alignment-control technology to assure correct and fast measurements. This has resulted in a throughput performance of 150 wafers per hour (5 points/wafer).
Options for the NRM-3000 include a stepper management system (analysis for registration, distortion, stepping, reticle rotation, and focus), the NSR focus mark measurement system, recipe management functions (network control for the creation, portability and storage of recipes and data), and arbitrary angle measurement (high speed and precision measuring of overlay marks at any angle).